@
jak
I don't think so, it's true that he always tries to come in between them, but not with bad intentions.
The characteristics are far different from the third person whose role is the oldest brother of all the series I've read.
Itsuki and her brother have had problems in the past and that's why.
Like a typical problem that starts with a misunderstanding, or not...a problem about a girl and such.
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Oh, damn, Itsuki is so cute lol
I really like it because they are always honest with each other rather than tugging and holding back throughout the story, leading to prolonged problems.